"Tang Mo was being kept at a petrol station in central Bangkok — confined to a chain, this poor guy had nowhere to hide away from the people, pollution or extreme temperatures," Wildlife Friends Foundation Thailand (WFFT) wrote. "Purchased as a pet when he was a tiny baby five years ago, it is likely that he was caught directly from the wild, witnessing the murder of his family or at least his mother."

The veterinarian spoke to the owners of the little macaque and convinced them that this was no life for an animal. Then he contacted WFFT, which dispatched rescuers immediately.

Sadly, what Tang Mo went through is all too common, as natural habitats where macaques live have been destroyed. And increased proximity to people means more macaques are taken from the wild and kept as pets.

But Tang Mo's time chained up and alone was about to come to an end. Rescuers arrived and took him to the WFFT rescue center.

"Upon arrival the first task was to remove the chain which was very tight around his neck. If not removed, a few months further down the line it would have ended up embedded within his neck," WFFT wrote. "After we removed the chain, a full health check was performed."

Luckily, Tang Mo is relatively healthy, considering all he's been through. But the emotional damage will take some time to heal. "Little Tang Mo bears the mental scars from his years in solitary confinement," WFFT wrote, "but with time he should be able to overcome some of this."